A big issue right now in the world of operating systems - especially Linux - is Microsoft's requirement that all Windows 8 machines ship with UEFI's secure boot enabled, with no requirement that OEMs implement it so users can turn it off. This has caused some concern in the Linux world, and considering Microsoft's past and current business practices and the incompetence of OEMs, that's not unwarranted. CNet's Ed Bott decided to pose the issue to OEMs. Dell stated is has plans to include the option to turn secure boot off, while HP was a bit more vague about the issue.

Ubuntu comes with an Office suite installed, so to match Ubuntu one would also have to purchase (at least) the following extra item as well:
Microsoft Office 2010 Home & Student [+$154]

So, for any option of Windows XP or Windows 7 the price would almost double, by the time you had purchased necessary software, compared to the Ubuntu option.

As long as Pioneer Computers is prepared to offer machines for sale without unwanted software bundled into the price, they are indeed worth of getting my custom.

For Windows 8 it would appear that Pioneer Computers may not be able to offer their customers the far better Ubuntu deal any longer. If that happens I would feel sorry for Pioneer Computers, but I would no longer buy from them, they would lose me as a customer. I would build up my own systems from piece parts if I have to.